| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device which keeps operation of a protection circuit and which prevents a high voltage from generating by releasing the protective operation at the time of exchanging a discharge lamp when the discharge lamp comes to the stage of non-lighting or to the end of the lifetime. SOLUTION: The discharge lamp lighting device is equipped with a detection circuit of a flow out filament 11, a detection circuit 12 of over-voltage to detect the end of the lifetime of the discharge lamp 10 and a detection circuit 13 of no-loading to detect non-mounting of the discharge lamp 10. If a flown out filament is detected or the over-voltage of the end of the lifetime is detected, due to this abnormal voltage, an inverter protection circuit 9 stops the inverter circuit 8, and when the discharge tube 10 is removed, the detection circuit of no-loading 13 detects the over-voltage caused by no-loading and a chopper protection circuit 5 stops a chopper circuit 3. |
